in_app_purchase.dart

  List<Widget> _button() {
    List<Widget> widgets = this
        ._items
        .map((item) => Container(
              margin: EdgeInsets.symmetric(vertical: 10.0),
              child: Container(
                child: Column(
                  children: <Widget>[
                    Align(
                      alignment: Alignment.bottomCenter,
                      child: Padding(
                        padding: EdgeInsets.all(ScreenUtil().setHeight(20)),
                        child: FlatButton(
                          onPressed: () {
                            this._requestPurchase(item);
                          },
                          child: Container(
                            height: ScreenUtil().setHeight(50),
                            width: ScreenUtil().setWidth(300),
                            padding: EdgeInsets.symmetric(
                                vertical: ScreenUtil().setHeight(15)),
                            alignment: Alignment.center,
                            decoration: BoxDecoration(
                                borderRadius:
                                    BorderRadius.all(Radius.circular(10)),
                                color: Colors.deepPurpleAccent),
                            child: FittedBox(
                              child: Text(
                                'Get for ${item.currency + item.localizedPrice}',
                                style: TextStyle(
                                    fontSize: ScreenUtil().setSp(20),
                                    color: Colors.white),
                              ),
                            ),
                          ),
                        ),
                      ),
                    ),
                  ],
                ),
              ),
            ))
        .toList();
    return widgets;
  }